The present invention relates to a self-powered flame monitoring apparatus that can be used in appliances having a gas burner, such as boilers, water heaters, and the like. In particular, this flame monitoring apparatus is suitable for use in portable or movable appliances, such as absorption-type refrigerators, that are adapted to be able to operate for prolonged periods in the absence of a regular power supply from power mains.
In portable appliances of the above cited type, the flame monitoring apparatus must have a prolonged operating autonomy, so that it should not be battery-operated. As a consequence, the flame monitoring apparatus usually comprises a thermocouple-based arrangement which, in response to the presence of the flame, energizes an electromagnetic gas-control valve. A display instrument is adapted to indicate the presence or absence of the flame. Since the electric power of such a thermocouple is very low, the display instrument must be of a very sensitive, highly responsive type. Such displays are undesirably delicate, fragile and expensive, i.e., unsuitable for use in a portable appliance.